SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd2b06a2f0131059533bf0fbc7bc94c76c77c328a4e32d2aea9b323e7f981eea9' 
  AND token = 'dv4J+RLxevmtYpESK8IB8Qp5dUZ31VnZjysigkReETw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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