SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a312c17a45e9e559cdcb7c7686804d7c3988c02086f2c9345dbf3b4d880edfbc' 
  AND token = 'ySv7fAu/Fr0VkWV3Hl3A1DBREjZM6GDTu4sKDUwcg4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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