SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7c99ee8839aca240cd971f40afb4097041e6e5676e30a17827ee0843e1e5ca9b' 
  AND token = 'ZUDroNvDv4niHnjBQyLN9rtll0WU6NrK2W+LYdHZn4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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