SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2deb025db2cf3c7bd00b816e2b9803cd475939cccd80e1e840a963bfd78251b' 
  AND token = 'uQU2c9rrw8PrA2dssHixFjlSJxM4iRxw6Xt+8pBFV8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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