SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3580227836c3a68188356addc7d7c0d10ff23dd83b85837d2feb480f0d4817b0' 
  AND token = 'yf0Ro9czy5QRh/sCgdMlekfr+SiUUu0Ty+xlXNX+oqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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