SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '43b04dce8067fa7d686eca45ceb07155edafec33095fa7e30d0e796b97165862' 
  AND token = 'KYK/8xfaZiih7SPzSA8syYRnjhKnyk9TeScKwd4v9jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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