SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d9520d8cb03a6533a86d6f266a0a8f3b21e7688cdfe878d68fc51cd459b43c9' 
  AND token = 'No6+quPIybDzzDa03KgWJi9Xb3GW/cb1GyPzbFII5hU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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