SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ac962e8ea591dd734287606d219473ce573891c8303ff59609f5d2fe5a812a66' 
  AND token = 'VZFxFOgd9ZzagTsKn5WNAzmCkDNEpFhhNo07F8gWZ74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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