SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2212e6f64963bcf2da7bf75d3668e392c3dfe8731dfef506cd5cfd40f27c5758' 
  AND token = '/pfaUAQrEPmqDi5GNyQpwzkfV6nvsclGqUTW+pHjHBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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