SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '151e33804d1603711ef1adadf4d3a033f898a695e286927cfdfa8b828df10f8e' 
  AND token = 'ypcqSBYFyrz5aw6jBmdn03JOWaeW3Za/2CUk3TqxxaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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