SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb4914c4a11f57fdf238e7c4c15f79d488687dfff99d1e0572a5bc4ea660bcf' 
  AND token = '4bGjWIlLWWT3gtWFR+gg2H/F+2wvfuOJKVnWXtJxLeg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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