SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e372a1e461e778285d63aab070b30e2f9544b47985e7a4d5c71c816f91fb229' 
  AND token = 'mJKlelXmLImMTACild/QT6YnyVxdhhhcfZuAKLRG4O4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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