SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9214c733fc2d9c73c9044b7296f181bee74abc039f7f2ccad7948ac90775bd7b' 
  AND token = 'SxM36dycnElfb554WrPA0kffkY0kPYUKjtxle4U69ic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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