SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c384b218e7270e06166a9cf4dd2b80eecacf2055c8a839985d7f0528634e4032' 
  AND token = 'uevBXMvfMOf2tEO0ll7VXUBzNyGkIMUHdpoIcVM7FqQ=' 
  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"
    }
  }
}