SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cc4047f3ec4f6206e18ff300be74dcb10d0cbe4eacbd6aa999367ccbad845f5' 
  AND token = 'f0/2sK3BnGLH4Roa3rurcTzMKos73zSZFRtj0ZyPs/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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