SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40cdfc6f3b39874643e5286de51536651f0a96ae4efe78c3e30190cb4120d1d1' 
  AND token = 'Q26p+WL3RcdeIlfSb+U/Yh/Ue1u4Yuq/dhvK6rvlIPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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