SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccabfa5e7660993d5f45cc4f07e14474c3a68f029147c0023763425fe3131a0b' 
  AND token = 'OxuFmpuvpHcVY3xYJ44xQfzXvBztEjzS5KR+9X6/VF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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