SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43d1c042bfec3b3705d5be2427030b3a7b9f7ed7d9bf6ebf41fb35221858458c' 
  AND token = '/24VholmAUPP79/vHf8FhkhLiHX5YwwjM6yYdVkBPEI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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