SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b382a69479e3537265313c554400c8a09c95c2a558670a5cf5fff1f20a3b1db' 
  AND token = 'Ot0QAqvLTGi+fMMCJokZtlI6KX1OYjHGuQI5oyfyC2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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