SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd36247e4df3e592831614f026a8933354a2d73bf1c481432c766a03d094f7f56' 
  AND token = 'cANBGXTYHGrBBaypRY6mVGPUPX30LAPgVMBoK0Bhz/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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