SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e5551b6c1f7138ccaf531f26a22cb63dda8b4784e0cf50f991a8632980e5c77' 
  AND token = 'kAeu/JzFFPTcDwiW7xgEaqw04W55PjT5zeXPIOU7GNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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