SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cec277bddc5af1923093ba88988b5a72cb66de0fee69d6526e2050cd04738bf2' 
  AND token = 'lQfAjOOin2a5KYCjEKV7m+yDpHv+i91tukt+lMoLIfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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