SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fbba6898f90a1ff8077211eed286dcec9e18a09eb4ae003a522fad814af770e' 
  AND token = 'WCoh4UEi74/IbRIU35Jkr54CwEJKpKHwGaH7LRY7iMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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