SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46e13a68687ba32ca60c5ad24adc68d15c89308100b7712e34024b621fffaf88' 
  AND token = 'wQiM2cyyFtf6PgPa4saMorPJjh/y0trqLdDRBjvYQgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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