SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34260132232ed8fec192312d35a3b67891db6e6e5b03804769e4c4425d67cf6c' 
  AND token = 'wvlJ9BKsvAKxN31GKqupFNlvONmULLS44ae7xkrFLcg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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