SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '77b570e90babdf90e80f1285ed5de66e609305c63552711454f64e6c51c92e95' 
  AND token = 'DUbMQdOzam91vgTdyX32MLHZSgtbn3YHjLyGrOtOvuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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