SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cce7ab76d61785287dd426aaa91583661433d90916801757cb38a817e1934292' 
  AND token = '9QUqHsKJWn3ZP2zB23Zr6BdzgJ3NgXUKn8NbYojBj0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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