SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9afe64d038991e514b7c7bff0a5918faa76e72b276a60f570c11200d0b5bfac' 
  AND token = 'VVfyhV+i+9ttlXSn1iAzSzc32dXOkRK1GWEWIaPJfQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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