SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2118997b6c348843a2c21c166f5db2b30df2baa1fe091259579f64af403ecd03' 
  AND token = 'xlw7rq/zFvquZBme8s9N2KzvI2Jcl1sC/c6M+XRMqrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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