SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '084e4dd1ac95fb652bc19f1d158669b7a723cb755887d754c501d42bd7fb20d7' 
  AND token = 'LrM7OhyAXnq1RWV9bryFg0KOFvzkuLJ9/2Uz2+fvYLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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