SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7b46dded5872dd9e5720a02cc1b3cb04071ca6dc147aef3d1c8cea205be2c2c3' 
  AND token = 'OGvXYuuKPhggP6YtkGFcVLVmtcZsxJ9+83RF2dXMUgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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