SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfa4322c7cd52366858dc2864538746c645585db434e963dcb77c70ceb253458' 
  AND token = 'c/Zf692hERC+VHzgswcXXnuiVIN1BSoEAa0oWFoNwCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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