SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3027a7baf81bd52bc62b4c6bb1cbc1a3151010c986c75fd8904fccf9f3cbaeb0' 
  AND token = 'gKliczDIuCidNMvwm44H+qhrK3EULUgTxjgEc/kn1AA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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