SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '539bd2523363a037d62194056c3b805c02b81d20df4f0ae84a84d6ccb14b76fb' 
  AND token = 'coKsa7FGXnHxLZX4OMedyYSqQGvkHVKQZ1XupbPf9hg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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