SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93b4ac9375a51906cad62cb7c4d1aa3252d7b416c15d0fd9646088855aff869a' 
  AND token = 'zdYJx+KBZjlOOg6kqmaZz+wLSzpx506SN4zdMwq5v1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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