SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce0d47b1264feb82e777153fc4a81e5a7962491932daedc8e2c39ddd3bdc9cae' 
  AND token = '86XQuPcbAOvZOFYoEs47f0rg1p7isnoRafo/jCQ/1aE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00111

JSON explain

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