SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5ef1b1bb09875940ec66f952e089f425b8f83b19db0378d7bfbdd497f6928f5' 
  AND token = 'uLPy9MXm7koqPVlKpdhrKnqsXrV21CPpdALXC/O08Uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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