SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d05bde73f2cb5c655d24f85e8a664cfd08b6b9e2574e8a7515aff98a2d3f775' 
  AND token = '6xzS1n4LmunB//vnTYa31UbCEAHBYUAqj1JgBHkmN04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00124

JSON explain

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