SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4f54ad4df129a63e9005c102670fb1d95d22ad1e14a08bc37bbcc6d6187564d3' 
  AND token = 'e9ceffURgplv/tet+3NkQvKe3I1G+SgS4hiC3zbmFdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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