SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'af2b97b9b386b1c11f370c6f0aef5e2d2da5ece131a029b555d660040c673fe8' 
  AND token = 'ytp2dCj04aMe+N77vqIPnICvBL61g8+kvHwZHVZ2Gk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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