SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b10be8c3dfe5f419dacdd6eb65ee481577851ffa8a5b6e3edb85f4c852a8a144' 
  AND token = 'GJkggY2zwucwUqaYUGMIXANviF/+BS1ShVzNEteolp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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