Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6a7eb3d2a71e6b673e9b0813bf32d4946a5de3e545e3618433c888d8107d7cb' 
  AND token = '4jAd0NOiTM85u+NM1JBGF23hY5SHrFYHBL3ynPUqcf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}