SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09bf624f0ee5c9ef9e74a2813741a8975841dee1540c27769841975631e19c7b' 
  AND token = 'gxjqGrCAinTruCSNFD9sTSlCCrHZrtiggb/HpqsDiys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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