SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05290fdc62682d6951b4e33cea5b18d7d1f8b3b121b25bec6dd83c943f95d775' 
  AND token = 'vls+qRiFvzbwpJyKrHCykdk6JsjRBbF+npEvJJrqFZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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