SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4e7b17d4941f74260dc6b8875157fc289bbf290690cf8dd847b66bab230761b' 
  AND token = 'ghNutXJaISb6qMMotZBKqVtLV79+crjQWwBJ4DPKsL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}