SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a7b2a912da181be359f3018a4e8ab09686b59685cbbe78d702abec794d482dcc' 
  AND token = 'I6ryZ2aYVKLtvhITGZyIXPp2iJoI2/bf2hByYMzKAB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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