SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c46547541bd3ba4c74c685176bb8b2f511f338a433790281eb21e2261c6fd9a' 
  AND token = 'HLlRfIqQz3SmjXrmOl653AIH9BugIv2DskIuqHrvR3k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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