SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'afe9e94bc40c6ed56d1172a1cfb477bb38751633932e8252a7ec5e262433f195' 
  AND token = 'wLVlNL3dHuOvz1r9ihvjgRj+4aILMonXXk0I/ErImYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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