SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba73fe1654c0bbba1f477240467f7e6ce7f2cc204fc1294b095f6a263e9d07a5' 
  AND token = 'uCvi6h2i77r/3Y8Av3Q4dIQi1Be9CkWj2/rzxfuTC0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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