SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '866067ff22cd2fa8e000508fbf022c814cdbfb282d2b3f260fdcce8f3b863e0b' 
  AND token = 'jeTvsIas8UxJe9i1s5GMnQjAnc+JPnSOZz4JyVePTzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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