SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b4cd162cc23a0b088261a6b22510f4b01b2a02132a14dd8a5a12a3e8046fe00d' 
  AND token = 'j0TibX9CYEpZ+EJHRAhbRcxOVIrmceukEIx1j9s8XQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}