SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '03481410da37373da17678f25e100460b95c86ab7ba41fcd2c4203e564f2bfe2' 
  AND token = 'SBuIseLR/eUbf/T2MBVJ21NRFvTn2MGQ6ihZIkWLzQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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