SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8888c310bb27992af2eccba6d28bc4e8d717b2f41738c8fb4c1dbcc4bd10d935' 
  AND token = 'maTbyNEqSuaPWhTM8vv7Hpy0ta7aNB2u6xqFWp2cwXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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