SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e37c9c62be185d4a793b64db7fa506e10906ec2ce017554e0bc58eb7278a2bad' 
  AND token = '2g2B36lYJq2kEzgpVJrtJHGsSPVidQDdxXzhfMGnEmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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