SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72826ff764579d16b0a5c71127f9dc7d2335bd6c594b9b5ce6fbdf1aff22f2a' 
  AND token = 'rIyYm1+xyIx6wTJY/jhGWmYENanGH8ZYVWAIJc1inL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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