SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '08708c85d03980de2496c1cfc1aa3b0ca54a3fddb9a26e3ee557049634d028f2' 
  AND token = 'RYd27pnNhgU1P8wCUFYxXlIaZ+Ytq+R17q8zMwiJius=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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