SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3311a5492d8fe374a8b7832857e1b2481125e966f1ea8fe7c935710fd6058bf3' 
  AND token = 'fV4ahqsRthZWyz9JPJUCKciXo81V3pbtpMZ0gyeGwLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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