SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7760f5bc06610d5a6e069244ff02ed0627dfcaff19100897807f6a0c958606f8' 
  AND token = 'Tf/JAeMUSDwk3Ta+btzqKqFuAcgSr/iIIoTLn5ScS68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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