SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a05e68679366d1dced4c0dc31ae3c78d183bc931481735cca784288fc7168fc' 
  AND token = 'Ba7HDTOWoYM9HBopvBpcJpu44lD6/QlUSSEVqWKPbs0=' 
  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"
    }
  }
}