SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b67bcd0d55ba3e0b776da101a98eacbabadfd130af7cc4b20b1bcad210c5934a' 
  AND token = 'LxwBRZoT7sfTYS2MhcHRAQUWs/7AiCvrQRnfm0qcYwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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