SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd94c11c11b48afafbbe6f8b213e4564b3d83f66c19f61b0ae2d8b8496107896' 
  AND token = 'T0dRJS11fETPUrY4vflR6My/vigjkfPM9sbZ7oiwtXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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