SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4346aeaf77f870bcba9ba2f9cbceda38d25b486042cb55e7e0a4b6e2440560f9' 
  AND token = 'VUaS+FN1kQhehD44fYH5NTXO/Qb35Q8WLzRpaEYb8VY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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