SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1659e23d180afd12858bbcce31f90fb1e64c0b8c7728d2fb3009f586cd7fff91' 
  AND token = 'F/GQsHzR+6CpyL5ZPCzXvVHEmNDIs0CjgZ3fZSaueR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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