SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a8c9dbe7962d4043aae96e3aba8b7523f90c457f17fb8fc5f64295003e7626f' 
  AND token = 'HDfYFL10LIyI222UQu6JqxndpXOKJVCZJzLvC5hSeqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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