SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c30bf105dffdb3561778544ea313a5ea8e34999c83d4fa8aa759e5eff8aead0' 
  AND token = 'JJUqMPfk8QhZ+HCFUQzQQKpOJ1Gae87yreC6PtRFtTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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