SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cd8c39d1811c9c4b25988a17a291b9dd7736381d038459bd934b7f13759b2c70' 
  AND token = 'KQ/5Kux/46puJIpAYKMYwTbqkgyH1h3fGDOB+O4jmHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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