SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b04ee95b15e003cdd161685e487207801d111afb00ece8f67904e0be78ee787' 
  AND token = 'Ah9Oyx66N9vdoyf0Vf6X5zbBIETwIAMR8iAvYFH4Xm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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