SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'af68f055da075e103b44014daa95dfc984609c952dca4622cac4b6550d02230c' 
  AND token = 'bB09sqQJ3IxLM6D/HCHmPoJX9AoA5jwj3uR7SBQqZbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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