SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89b58d9d5ed6461d16ba4ef9b18eec836022ca6f7ff0635391c4ec6227061362' 
  AND token = 'foNVe6aqx3tQqUCAzZRkwJExaeyYae+8kD/bFB5TewY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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