SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70f057647ce6ef827e8f5844330084f9ff4c5871666409eb2143bd1e29a1534f' 
  AND token = 'prYs5UcTQ1tkLxnNqhFRJIe58sKagxaBzFDs5fJq8Bo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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