SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7eb9ef651cd055f411ae8b92295843634407626d68f4197d82820b7acfe12676' 
  AND token = 'uPJPnqF665LvBLXxhx3Yj4670hxpfXZnM7AypLQdFxM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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