SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9dcbe6bf155fcd5bd88109f1be45c0a894f6029241fa6c12ed6b3ce5e7f2354b' 
  AND token = 'iV7ukakWhWc3JlA5sPOBg7N2Jck+8HSB8wr4j3O4HCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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