SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e022e31f4b4e6d7a0d9a3ba858b04abc066e58a749df9eab38c694bf4bdbe8b6' 
  AND token = 'niXVkJTOaFMjqHC9RIqEsJwhWee9MrIghEGBCn2a1bI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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