SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c80e96c2356e27863a4a1feba022c85766c107d8c98be2765d7b37856c20fa8' 
  AND token = 'fFGRAf+clT6q/+8B08WInUljhGCCfNOruiqrhQFE5nI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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