SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f47fa860add2ec1221a0d458a42f9750fe2c75b9b252aaf932003462846a323' 
  AND token = 'sR0V/AEJ6S3YByW/5nRP7tGWQwKqDy3/rJTmPsqwYhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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