SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10ce4b64a6c50ae3ff46fb642c6204e90ee57759934ab0ac586325396dc6a78d' 
  AND token = 'rgXlgscUOhppa1T7Yg0KMo6KZLOPkJRVmDbi2Xf7yz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}