SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e06cbd7d30992721f33b432d8691953d94f2cdf8cc93f21c98da2e5148806347' 
  AND token = 'LT6Be1csAfnNnh0qTbFVSn1bSFhruHnZD4nJN4GqyH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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