SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e1edaef0d073163c301989044b910d3493ca1e3a15c1f33c750aadcd73daffd1' 
  AND token = '6acVxms7cVuC3zkpw/s2w86UgDx3thbvgRZGPDh37+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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