SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5aa140c67776453395c20f43b13e07905fe318b5c58b1d403257589c99d60085' 
  AND token = 'wxUOV+9QVpL1vgdpaDJquiH1poO3MNkvyg/NKz+Ru04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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