SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06795ceeeaf3a3197e47110c624a64ae305bb4387e519caa3dcbad96ab08070c' 
  AND token = 'kQf/8LlgUwrkZwr58G6aKGbZvZIPfIm/OMFmyqwowCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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