SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae78586d24234ddd4d75194839db9c848f951b1301e02978ea24041656078bdc' 
  AND token = 'eO9Y+folhYd4Y4EwMan5MhziWSSNb45pPQWyPvfXZN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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