SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2084703b53a6c909ed6ab049c5128d66a75a170f21a5790beba193d6a5fe2a55' 
  AND token = 'VAli7xgW6KSHQyBNjHfNwixLsUQN8PIY0Zj7JvuNvPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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