SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f93b4a4184c5525d77c78bb13ed0ba122c9d23315256f427e8be900e09f3acdd' 
  AND token = 'YBNcvmJqeAI5nOeqnMIEC5ly3mp7hTd6k15rBLtSwhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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