SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4589408a1da00e5d69fa8cffee03f56d3e4fa47fca7b6ef489594e4f568f9a6b' 
  AND token = 'm4cLkIpBgulhB34X0KYXRg7Sw6ALHJGz+448UpTO66E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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