SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8572785827d28d9b03aa37d066ab3102e0db66d3d34a8fc45a012d8f34cb1fae' 
  AND token = '0YXlQObRQY2xqxebelPJjANcJztIweYGX9ccTjsmWnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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