SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26776b60206a21655527fe9e81147bb2c48ada10683c44abd229503475238266' 
  AND token = 'aIHZqDw3qSYStilAEM/ibmgw9Cw1yoaWSidf4TroafA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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