SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f0742da0b01f924e7232e912e3d3af3b8e17df8931bfd35aee5911af90591df' 
  AND token = 'iDLUiqb7qLUEsTK+udSX7QP8Zzh7BDB7kR2ZyJ5+za0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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