SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fae2f0b820cffedccbb0ce4d758c72fe7fe5fc519eadb2f2d0bf28188df5d5d' 
  AND token = 'SawkymkwNEdfqQxMyK23IkQyUCiVgA39zyXMHN9V0e4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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