SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a73c04b7b55352f75185e83e7a56d5cebd06220a53b80db2d7292c4e4780539' 
  AND token = 'EbEZphMez/WZCashUjtZorhuQFmu+58DFWLy57SQbuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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