SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13e05290c6d7636dbf7ebd3a964751ce7e46a6438083658697500b52d533b8b8' 
  AND token = 'jt/HU374houVq+mEq9gr6CzaqFiICptxlhDNMCVvnX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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