SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d23580e1c21d290df49cc904bf41e9a53032fbcb0efae9f11c8426de872123a' 
  AND token = '/HaiY2k9LAjLvfntNVZJP9gR8s0F/+GyRSsyrKOlb/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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