SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2474a81a7829b9068be12d7f17318847ea1dbedf76bd5a6374b4b98e7417857c' 
  AND token = 'G4rrJvOrrEN/l7yjuHoGTkmDfFNUcuL2Sd0EvzuiIMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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