SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb8402b85d95fe4bdbbfd4175a5932814cdf74c5c2071e27c6d3ff4b4d4927c9' 
  AND token = '6vXuWfKXXa1y8zBBsWQqvKtV+z3WhWNrIBs2XSjzyP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 1.49863

JSON explain

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