SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1994c7da4607ff5653dab3e919020fb142566641e75f07d114915be17d3935a' 
  AND token = 'MfRbdTgYVXrNbO/Fyg3rR0nagNNJhdnJbTIfTYCYRIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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